Engine Systems Basics Raffi Hedinger Hansi Ritzmann Beitrag für einen geregelten Warmlauf bei Ottomotoren Raffi Hedinger Dimitri Mankov Christopher Onder
Engine Systems Team Chris Onder Professor Hansi Ritzmann PhD Student Raffi Hedinger PhD Student 2
Topics Today Engine Systems Lecture some Basic Information Actuators and Working Principle of Internal Combustion Engines Gasoline vs. Diesel Engines Tour through Engine Hallway ML E
Engine Systems Lecture Lecture Focus on control oriented modeling of the engine no detailed thermodynamics, fluiddynamics or mechanics Based on class textbook Introduction to Modeling and Control of Internal Combustion Engine Systems by Guzzella, Onder Exercises Studentsdevelop a multivariable idle speed controller and test in on a real engine 1 hour exercise class per week, based on exercise instructions manual Exam Oral exam, 30 minutes Tests your understanding of all the material covered in lecture and exercises Note: other lecture by Prof. Onder: «Vehicle propulsion systems» Focus on control oriented modeling of entire vehicle and different propulsion systems
Internal Combustion Engines World s largest marine Diesel engine 30 meters long 8000 PS per cylinder 115 000 PS in total
Simplified model of a gasoline engine IC Intake manifold Exhaust manifold Engine block
Simplified model of a gasoline engine Fuel pump ET Injection FP IC Ignition coil Valves Throttle Exhaust manifold Intake manifold Engine block
Simplified model of a gasoline engine MA Fuel pump ET TA PM Injection FP IC Ignition coil Valves l 1 l 2 Throttle AK TE Exhaust manifold Intake manifold Engine block AK CP IC MA SE FP knock sensor camshaft sensor ignition command air mass-flow sensor engine speed sensor fuel pressure control PM ET TA TE CC l 1,2 manifold pressure sensor VE electronic throttle SA intake air temperature sensor TWC cooling water temperature sensor ECU active carbon canister CCV air/fuel ratio sensors DP EGR valve secondary air valv 3-way catalyst controller CC control valves driver pedal
Simplified model of a gasoline engine MA ET TA PM FP IC CP l 1 l 2 AK TE AK CP IC MA SE FP knock sensor camshaft sensor ignition command air mass-flow sensor engine speed sensor fuel pressure control PM ET TA TE CC l 1,2 manifold pressure sensor electronic throttle intake air temperature sensor cooling water temperature sensor active carbon canister air/fuel ratio sensors VE SA TWC ECU CCV DP EGR valve secondary air valve 3-way catalyst controller CC control valves driver pedal
Simplified model of a gasoline engine MA ET TA PM VE FP IC CP l 1 l 2 DP CCV AK TE SA CCV CC Tank SE AK CP IC MA SE FP knock sensor camshaft sensor ignition command air mass-flow sensor engine speed sensor fuel pressure control PM ET TA TE CC l 1,2 manifold pressure sensor electronic throttle intake air temperature sensor cooling water temperature sensor active carbon canister air/fuel ratio sensors VE SA TWC ECU CCV DP EGR valve secondary air valve 3-way catalyst controller CC control valves driver pedal
Simplified model of a gasoline engine QA Fuel pump ET Injection FP IC Ignition coil Valves Throttle Exhaust manifold Intake manifold Engine block Q: Which actuators are required for the basic operation of a (4-stroke) gasoline engine? A: Air path Throttle Intake and exhaust valves Fuel path Fuel pump Fuel injector Ignition Ignition coil Spark plug
Simplified model of a gasoline engine QA Fuel pump ET Injection FP IC Ignition coil Valves Throttle Exhaust manifold Intake manifold Engine block Q: Why can the engine be intrepreted as a volumetric pump? A: It pumps a certain volume (the displacement volume) of air from the intake manifold to the exhaust manifold
4 Stroke Engine The four strokes: 1. Intake Stroke 2. Compression Stroke 3. Power Stroke 4. Exhaust Stroke One engine cycle consists of two revolutions
4 Stroke Engine, pv-diagram Minimum volume Maximum volume Calculating Work WW = FF dddd = pp dddd log-log scale linear scale Positive work This is what we want Negative work Losses (pumping work) negative Work
2 Stroke Engine Compression strokeand power stroke combined Exhaust strokeand intake strokeare combined, inflowing air washes out exhaust gas. Engine cycle consists of one revolution
Mechanical System
Gasoline & Diesel Engines Gasoline Diesel Air Fuel Spark Ignition SI Engine Compression Ignition CI Engine
Gasoline & Diesel Engines Gasoline Diesel Air Fuel Low power Low power «Quantitative Control» «Qualitative Control» High power High power
Smplified pv-diagrams
Gasoline & Diesel Engines QA Is the combustion in a Diesel engine stochiometric? No! There is always excess air Is a throttle required for the basic operation of a Diesel engine? No! The power is controlled by the amount of injected fuel What is the effect of pressing the gas pedal in a Diesel and gasoline engine resprectively? Diesel: Inject more fuel Gasoline: Opening of throttle, more air gets into cylinder, controller then injects more fuel
Self Induction & Forced Induction Engines Self induction/ naturally aspirated Forced induction/ super charged Air is taken in by the down stroke of the cylinder which results in a pressure drop in the intake manifold Air is forced into the intake manifold by the charger
Self Induction & Forced Induction EnginesQA Q: Why does forced induction lead to higher specific power (W/kg)? A: For the same displacement volume = same engine weight, more fuel can be burned, more power is generated Q: Where is the power taken for the compressor in forced induction? A: Turbocharger: energy from exhaust gas A: Mechanical compressor: energy from engine shaft
Thank you for your attention Let s go see the engines on the ML E floor Beitrag für einen geregelten Warmlauf bei Ottomotoren Raffi Hedinger Dimitri Mankov Christopher Onder